diff --git a/.github/actions/install_smithy_dafny_codegen_dependencies/action.yml b/.github/actions/install_smithy_dafny_codegen_dependencies/action.yml
index 89971fdf7..d7900e05f 100644
--- a/.github/actions/install_smithy_dafny_codegen_dependencies/action.yml
+++ b/.github/actions/install_smithy_dafny_codegen_dependencies/action.yml
@@ -8,14 +8,40 @@ description: "Install Java package dependencies required to run Smithy-Dafny cod
 runs:
   using: "composite"
   steps:
-    - name: Install smithy-dafny-codegen Rust dependencies locally
-      uses: gradle/gradle-build-action@v2
+    - name: Setup Java 17 for codegen
+      uses: actions/setup-java@v3
       with:
-        arguments: :codegen-client:pTML :codegen-core:pTML :rust-runtime:pTML
-        build-root-directory: mpl/smithy-dafny/smithy-dafny-codegen-modules/smithy-rs
+        distribution: "corretto"
+        java-version: "17"
 
-    - name: Install smithy-dafny-codegen Python dependencies locally
-      uses: gradle/gradle-build-action@v2
+    - name: Install smithy-dafny-codegen dependencies locally
+      shell: bash
+      run: |
+        make -C mpl/smithy-dafny mvn_local_deploy_polymorph_dependencies
+
+    - name: Setup Python, black, and docformatter for code formatting
+      uses: actions/setup-python@v4
+      with:
+        python-version: ${{ matrix.python-version }}
+        architecture: x64
+    - shell: bash
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install --upgrade black
+        python -m pip install --upgrade docformatter
+
+    - name: Install Go
+      uses: actions/setup-go@v5
       with:
-        arguments: :smithy-python-codegen:pTML
-        build-root-directory: mpl/smithy-dafny/codegen/smithy-dafny-codegen-modules/smithy-python/codegen
+        go-version: "1.23"
+
+    - name: Install Go imports
+      shell: bash
+      run: |
+        go install golang.org/x/tools/cmd/goimports@latest
+
+    # Without this the if-dafny-at-least command includes "Downloading ..." output
+    - name: Arbitrary makefile target to force downloading Gradle
+      shell: bash
+      run: |
+        make -C mpl/StandardLibrary setup_net
diff --git a/.github/actions/polymorph_codegen/action.yml b/.github/actions/polymorph_codegen/action.yml
index 4eed3a9c5..c43cc1b5c 100644
--- a/.github/actions/polymorph_codegen/action.yml
+++ b/.github/actions/polymorph_codegen/action.yml
@@ -57,6 +57,12 @@ inputs:
 runs:
   using: "composite"
   steps:
+    - name: Install smithy-dafny dependencies
+      shell: bash
+      working-directory: mpl/smithy-dafny
+      run: |
+        make mvn_local_deploy_polymorph_dependencies
+
     - name: Update MPL submodule locally if requested
       if: inputs.update-and-regenerate-mpl == 'true'
       shell: bash
diff --git a/.github/workflows/library_dafny_verification.yml b/.github/workflows/library_dafny_verification.yml
index a90d5fa6a..6f94c7eb2 100644
--- a/.github/workflows/library_dafny_verification.yml
+++ b/.github/workflows/library_dafny_verification.yml
@@ -48,7 +48,6 @@ jobs:
           dafny-version: ${{ inputs.dafny }}
 
       - name: Install Smithy-Dafny codegen dependencies
-        if: ${{ inputs.regenerate-code }}
         uses: ./.github/actions/install_smithy_dafny_codegen_dependencies
 
       - name: Regenerate code using smithy-dafny if necessary
diff --git a/.github/workflows/library_java_tests.yml b/.github/workflows/library_java_tests.yml
index 4ab45937d..80c3b7d68 100644
--- a/.github/workflows/library_java_tests.yml
+++ b/.github/workflows/library_java_tests.yml
@@ -54,7 +54,6 @@ jobs:
           dafny-version: ${{ inputs.dafny }}
 
       - name: Install Smithy-Dafny codegen dependencies
-        if: ${{ inputs.regenerate-code }}
         uses: ./.github/actions/install_smithy_dafny_codegen_dependencies
 
       - name: Regenerate code using smithy-dafny if necessary